1 / 17

Introduction to the OAI Protocol for Metadata Harvesting Version 2.0

Introduction to the OAI Protocol for Metadata Harvesting Version 2.0. Hussein Suleman Virginia Tech DLRL 17 June 2002. Version 2.0. Already ? Why ? What are you guys thinking ? But we didn’t implemented version 1.1 yet! OK, so what is it anyway ?. Already ?. Released 14 June 2002

helki
Download Presentation

Introduction to the OAI Protocol for Metadata Harvesting Version 2.0

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to the OAI Protocol for Metadata HarvestingVersion 2.0 Hussein Suleman Virginia Tech DLRL 17 June 2002

  2. Version 2.0 • Already ? • Why ? What are you guys thinking ? • But we didn’t implemented version 1.1 yet! • OK, so what is it anyway ? OAI-PMH v2.0

  3. Already ? • Released 14 June 2002 • Detailed schedule • Alpha test - since 1 March 2002 • Beta test - 1 April 2002 • Expected release - 1 June 2002 • Many alpha and beta testers OAI-PMH v2.0

  4. Why ? • v1.0/v1.1 was experimental • v2.0 should be stable • Some minor shortcomings in semantics of v1.1 • Encoding issues that could be fixed OAI-PMH v2.0

  5. But we didn’t implement v1.1 yet • That’s OK! • v2.0 is not very different and in fact simpler for some things • Existing archives need not upgrade as long as harvesters understand multiple versions of the protocol ! OAI-PMH v2.0

  6. Some New “Features” • Single schema • ListIdentifiers changes • Provenance containers • Granularity of harvesting • Orthogonality of setSpecs • More flow control • XML error codes • Timezones • resumptionToken idempotency OAI-PMH v2.0

  7. XML Error Codes • <error code=“badArgument”>… </error> • badArgument, badResumptionToken, badVerb, cannotDisseminateFormat, idDoesNotExist, noRecordsMatch, noMetadataFormats, noSetHierarchy • Errors within the regular responses - no more HTTP 404s • Philosophy: separation of PMH and HTTP OAI-PMH v2.0

  8. Single Schema • Use standard schemas where available e.g., Dublin Core from DCMI and MARC from LoC • Use single namespace and schema for all requests/responses • No more arbitrary restrictions on format of metadataPrefix, setSpec, etc. OAI-PMH v2.0

  9. New Response Format • <OAI-PMH> <responseDate>… <request parm1=“...” parm2=“…”>… <GetRecord> … <GetRecord></OAI-PMH> • <OAI-PMH> <responseDate>… <request parm1=“...” parm2=“…”>… <error code=“”></OAI-PMH> OAI-PMH v2.0

  10. Orthogonality of setSpecs • Previously you could not find the sets that an item belonged to • Now, every record header must include setSpecs • <record> <header> <identifier>…</identifier> <datestamp>…</datestamp> <setSpec>cs</setSpec> <setSpec>math</setSpec> </header> OAI-PMH v2.0

  11. ListIdentifiers Changes • metadataPrefix is a required parameter • the records in different formats may be updated independently • More information returned - complete headers instead of identifiers • datestamp, identifier, status, setSpec OAI-PMH v2.0

  12. Provenance Containers • <about> is now a repeatable field • Special provenance container for historical information - esp. w.r.t hierarchical harvesting • <provenance> <originDescription harvestDate=“…” altered=“true”> <baseURL>…</baseURL> <identifier>…</identifier> <metadataPrefix>…</metadataPrefix> <datestamp>…</datestamp> <harvestDate>…</harvestDate> </originDescription></provenance> OAI-PMH v2.0

  13. Granularity of Harvesting • Now supports times in addition to dates! • Finest granularity in Identify response • Formats: • YYYY-MM-DD • YYYY-MM-DDThh:mm:ssZ • Must support coarser granularities • Error on finer granularities OAI-PMH v2.0

  14. More Flow Control • resumptionTokens now take additional optional parameters for better flow control • completeListSize • cursor • expirationDate OAI-PMH v2.0

  15. Timezones • Everything is now explicitly GMT • If you use local dates, you may need to delay new entries to ensure stable harvesting • If all sites use GMT, there will be no need to overlap dates by 1 day to cater for timezone differences OAI-PMH v2.0

  16. resumptionToken idempotency • resumptionTokens can be sent repeatedly to a server and the response should be identical (or supersets) • This helps with mid-stream errors in harvesting from large archives OAI-PMH v2.0

  17. Now What ? • Updated toolkits are gradually being announced on OAI-Implementers list • Repository Explorer/ARC/OAIA were all compliant before release ! • Future Work • Experiments and Extensions • SOAPification • Other protocols OAI-PMH v2.0

More Related